BY SIMON PERRY

In a historical moment that marked a shift in her 65-year reign, Queen Elizabeth relinquished the duty of laying a wreath on her behalf for Britain’s fallen soldiers to her son, Prince Charles.

Instead, she chose to stand alongside her husband of almost 70 years as they watched their son take on the sacred duty at the annual Remembrance Sunday service.

Charles, 68, performed the somber ceremony as the Queen, 91, and Prince Philip, 96, looked down from a balcony of the Foreign and Comonwealth Office in London.

This year marks the first time she has been present at the ceremony and not laid a wreath. She has missed the event only six times previously in her record-setting reign – when she was out of the country or pregnant with sons, Prince Andrew and Prince Edward.

Since Philip retired from royal duties in August, he chose to make his tribute from the sidelines. And the Queen followed his lead, wishing to stand with him. Camilla, Duchess of Cornwall, also joined them in the balcony.

Sophie Wessex and Princess Alexandra watched from a separate balcony with Kate Middleton, who looked on as Prince William and his brother Prince Harry also each laid a wreath in front of politicians, military leaders and veterans.

After the wreaths were laid, around 10,000 servicemen and women and veterans marched along the grand London street.

Insiders have highlighted the fact that standing in the windy, often-chilly street and then laying the flowers and making the solemn few steps backwards is one of the royal family’s most poignant traditions — and one that was likely often a test for the Queen.

“After taking her oath in Westminster Abbey in 1952, to lay the wreath on behalf of millions of people killed in the First World War and subsequent conflicts is probably the most solemn thing she does as Sovereign,” a former member of her household tells PEOPLE. “I think the psychology of having Prince Philip behind her made that little walk back a little bit easier for her.”

Handing over the duty to Charles also provides a chance for her son and heir to take a leading role in a national celebration.

“It is a good moment to give Prince Charles a highly symbolic and highly ceremonial act of monarchy,” the former member of her household adds. “The public thought it was completely natural with her being 91.”

The Queen’s decision to step back from the ceremony in the same year as her husband is “a sign of their partnership,” Robert Lacey, author of a companion book to Netflix’s The Crown, tells PEOPLE. “She could have vowed to keep on doing it, and he is probably fit enough to do it too, but the two of them are working together to allow Charles forward.”

Ahead of Sunday’s ceremony, the Queen and and many members of the royal family, gathered with veterans, and their relatives and friends, for the Festival of Remembrance on Saturday evening at London’s Royal Albert Hall.

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